JP2008307701A - Manufacturing method of tube made of fiber-reinforced resin and tube manufactured by the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the unwinding of a prepreg, without deteriorating the lightweight nature of a tube made of a fiber-reinforced resin and thus to enhance the strength thereof and the productivity therefor. <P>SOLUTION: The method comprises the process of winding a bias prepreg 21 or 22, a straight prepreg 23, 25, 27 or 28 and a hoop prepreg 24 or 26 on a core material each at least by one sheet. Of the hoop prepreg 24 or 26 at least one is in advance laminated/tightly attached onto a base prepreg consisting of the bias prepreg 21 or 22 or the straight prepreg 25 or 27, to form a laminate A1 or A2, and by winding the laminate A1 or A2 the hoop prepreg 24 or 26 is wound integrally with the base prepreg 25 or 27. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for producing a tubular body made of fiber reinforced resin and a tubular body made of fiber reinforced resin produced by the method, and in particular, to prevent poor stacking of tubular bodies using a hoop prepreg.

In recent years, materials for tubular bodies such as golf club shafts and fishing rods are mainly fiber reinforced resins such as carbon prepregs that are lightweight and have high specific strength and high specific rigidity.
These tubular bodies made of fiber reinforced resin are generally formed by laminating fiber reinforced prepregs, and fiber reinforced prepregs have the following different characteristics depending on the arrangement direction of the reinforced fibers.
In the bias prepreg in which the arrangement direction of the reinforcing fibers is inclined with respect to the axial direction of the tubular body, since the fibers extend in a spiral shape, the torsional rigidity and the torsional strength can be mainly increased.
The straight prepreg in which the arrangement direction of the reinforcing fibers is arranged substantially parallel to the axial direction of the tubular body can mainly increase the bending rigidity and the bending strength because the fibers extend in the tubular body axial direction.
In the hoop prepreg in which the reinforcing fibers are arranged in a direction substantially perpendicular to the axial direction of the tubular body, since the fibers extend in the circumferential direction of the tubular body, the crushing rigidity and the crushing strength can be mainly increased.

In manufacturing a tubular body, a technique is known in which the bias prepreg, straight prepreg, and hoop prepreg are used in combination to adjust rigidity and strength necessary for the tubular body while maintaining light weight.
For example, in JP-A-8-131588 (Patent Document 1), as shown in FIG. 5, a bias layer 2 made of a bias prepreg is arranged on the outer side, and a straight layer 3 made of a straight prepreg is arranged on the inner side. Further, a golf club shaft 1 provided with a hoop layer 4 made of a hoop prepreg is proposed on the inner side of the golf club shaft, whereby the torsional rigidity and bending rigidity of the golf club shaft 1 can be increased without impairing the lightness. ing.

However, the hoop prepreg has a feature that it is difficult to wind the hoop prepreg because the bending of the reinforcing fiber extending in the circumferential direction is suppressed during winding. For this reason, it is difficult to laminate the hoop layer and the lower layer thereof, and end portions are easily peeled off.
When such unwinding occurs, the hoop layer is lifted, the prepreg is bent in the winding operation of the outer peripheral layer, and an air pool is generated at the lifted portion, so that the strength is lowered and the characteristics of the tubular body are also varied. This is problematic in that it causes quality degradation. In addition, since it is necessary to re-adhere such a defective portion, there is a problem in that productivity is lowered.

  As a countermeasure to the above problem, there is also known a method in which a straight layer is disposed on the outer peripheral side of the hoop layer and the number of windings (PLY number) of the straight layer is increased to prevent a hoop layer stacking failure by a lapping effect. However, since a tubular body such as a golf club shaft has a strong demand for weight reduction, it is necessary to eliminate the surplus of the straight layer. Moreover, in order to prevent a reduction in strength due to weight reduction, the hoop layer is expected to be multilayered in the future, and the straight layer is required to have the same number of turns as the hoop layer at most.

JP-A-8-131588

  The present invention has been made in view of the above problems, and is manufactured by a method of manufacturing a fiber-reinforced resin tubular body capable of preventing unwinding of a hoop prepreg without impairing lightness and improving quality and productivity, and the method. It is an issue to provide a tubular body.

In order to solve the above problems, the present invention provides a method for producing a tubular body made of a fiber reinforced resin comprising a laminate of prepregs obtained by impregnating a reinforcing fiber with a matrix resin.
Bias prepreg in which the arrangement direction of the reinforcing fibers is inclined with respect to the tubular body axis, a straight prepreg in which the arrangement direction of the reinforcing fibers is arranged in parallel to the tubular body axis, and the arrangement direction of the reinforcing fibers are tubular A step of winding a hoop prepreg arranged at right angles to the body axis on a core material;
At least one of the hoop prepregs is formed as a laminated hoop prepreg (hereinafter referred to as a laminated hoop) to form a laminated body in which the bias prepreg or the base prepreg made of the straight prepreg is laminated and adhered in advance, and the laminated body is formed. A method for producing a tubular body made of fiber reinforced resin is provided, wherein the laminated hoop is wound integrally with the base prepreg.

According to the method for producing a tubular body of the present invention, a hoop prepreg that is difficult to wind around a core material is laminated and adhered in advance to a straight prepreg or bias prepreg that is easy to wind to form a laminated hoop as a laminated body. As a result, it is possible to prevent the stacking failure such as peeling off, which is likely to occur when the hoop prepreg is wound alone, while maintaining the light weight of the tubular body without increasing the number of windings of the base prepreg. Quality and productivity can be improved.
In addition, it is good also as a laminated body which laminated | stacked and adhered the hoop prepreg beforehand on both sides of the straight prepreg or the bias prepreg.

When a plurality of hoop prepregs are used, it is preferable that all the hoop prepregs are the laminated hoops.
Moreover, since a straight prepreg is easier to wind than a bias prepreg, it is preferable to use a straight prepreg as the base prepreg constituting the laminate.
Furthermore, when winding the laminated body around the core material, it is preferable to wind the base prepreg so that the base prepreg is on the outer peripheral side of the laminated hoop in consideration of the wrapping effect of the base prepreg.

In addition, the hoop prepreg in this invention points out that the crossing angle of the arrangement direction of a fiber and a tubular body axial direction is 80-100 degree | times.
Further, the straight prepreg refers to those having an intersection angle of −10 to +10 between the fiber arrangement direction and the tubular body axis direction.
Further, the bias prepreg refers to a fiber having an intersection angle between the fiber arrangement direction and the tubular body axis direction of more than 10 degrees and less than 80 degrees, more than -10 degrees and less than -80 degrees.

At least one of the both ends in the tubular body axial direction and the winding end edge of the laminated hoop that is laminated and adhered to the base prepreg is made to coincide with the peripheral edge of the base prepreg, or the base prepreg is more than the peripheral edge of the base prepreg. It is located inside.
As a result, the anchor effect of the base prepreg can be expressed at the end of the tubular body axial direction and / or the winding end edge where the hoop prepreg is particularly likely to be unwound, and the winding operation is facilitated. Stacking failure can be prevented more reliably.

  The laminated hoop is preferably located at the inner edge of the base prepreg at the same position as the peripheral edge of the base prepreg at all three positions of the both end edges and the winding end edge in the tubular body axial direction. In addition to the three places, it is more preferable that the winding initial end edge of the laminated hoop coincides with the periphery of the base prepreg or is located inside the base prepreg. This is because, if only the winding initial edge of the peripheral edge of the laminated hoop is located outside the base prepreg, only the rigidity of the winding initial edge is reduced, and stress is concentrated, making it easy to bend or bend. It depends.

  Moreover, it is more preferable that the peripheral edge of the laminated hoop is positioned inside the base prepreg than the peripheral edge of the base prepreg. The anchor effect by the peripheral part of the base prepreg can be expressed more effectively, and the stacking failure of the hoop prepreg can be prevented more reliably.

The peripheral edge of the laminated hoop and the peripheral edge of the base prepreg should be separated from each other by 1 mm or more, further 3 mm or more, further 5 mm or more, more preferably 10 mm or more. This is because the anchoring effect of the base prepreg can be sufficiently exerted by separating the peripheral edge of the laminated hoop and the peripheral edge of the base prepreg, stress concentration on the peripheral part of the laminated prepreg can be prevented, and the tubular body can be prevented from being broken. It depends.
On the other hand, if the peripheral edge of the laminated hoop and the peripheral edge of the base prepreg are separated too much, the length of the laminated hoop is shortened and the crushing rigidity / strength is reduced, or the base prepreg is unnecessarily large, resulting in an increase in weight. The separation distance is 50 mm or less, further 30 mm or less, and more preferably 20 mm or less.

  The present invention provides a tubular body manufactured by the above method, wherein both end edges of the laminated hoop in the axial direction of the tubular body are located on the inner side of both end positions of the final product of the tubular body. Yes. This is because hoop prepreg unwinds easily when the tubular body axial end of the hoop prepreg is located at the end of the tubular body itself, and the golf club shaft, fishing rod, etc. The end product of the hoop prepreg is positioned at the end of the product in the state of the final product after both ends are cut because the end product of the end product is cut to the required dimensions. Because it is required not to.

  When laminating the laminated hoop partially shorter than the entire length of the tubular body, it is preferable to cut the edge of the laminated hoop in the tubular body axial direction obliquely with respect to the tubular body axial direction. Thereby, since the lamination | stacking level | step difference after shaping | molding can be relieve | moderated, the stress concentration to the both ends of a hoop layer can be prevented, and the strength reduction of a tubular body can be suppressed.

The laminated hoop preferably has a thickness of 0.03 to 0.06 mm.
The thickness of the laminated hoop is 0.03 to 0.06 mm. If it is less than 0.03 mm, it is too thin and the crushing rigidity / strength is insufficient. If it exceeds 0.06 mm, it becomes too thick and lamination becomes difficult. This is because the end portion is likely to be insufficiently adhered.

Moreover, it is preferable that the tensile elastic modulus of the reinforcing fiber of the laminated hoop is 30 to 80 ton / mm ² . The tensile elastic modulus here is measured in accordance with JIS R7601: 1986 “Carbon fiber test method”.
What the tensile modulus of the reinforcing fibers of the laminated hoop and 30～80Ton / mm ² is, 30 ton / mm not obtained the required crushing rigidity / strength of less than ^2, it exceeds 80 tons / mm ^2, the elasticity of the fibers This is because it becomes too strong and lamination becomes difficult.

The resin content of the laminated hoop and / or base prepreg is preferably 30 to 40%.
This is because if less than 30%, the laminate adhesive strength of the laminate hoop itself decreases, and if it exceeds 40%, the laminate hoop becomes too thick, resulting in an increase in weight, and a laminate step becomes large, resulting in stress concentration and poor appearance. It depends on.
Preferably, the resin content is set to 30 to 40% for both the laminated hoop and the base prepreg.

  In the present invention, five or more hoop prepregs may be used, but considering the balance between weight increase suppression and bending strength / torsion strength maintenance, 1 to 4 sheets, more preferably 1 to 3 sheets, Two sheets are preferable.

  It is preferable to use 2 to 8 bias prepregs, and more preferably 4 to 6 sheets. If less than 2 sheets, the torsional rigidity / strength will be weak, and if 1 sheet, the torsional rigidity will be asymmetrical. If more than 8 sheets, the ratio of other straight prepregs and hoop prepregs will be small within the limited weight. This is because the bending rigidity / strength and crushing rigidity / strength decrease.

  It is preferable to use 1 to 8 straight prepregs, more preferably 2 to 6 sheets, and more preferably 2 to 4 sheets. This is because if the number is less than one, the torsional rigidity / strength is insufficient in addition to the bending rigidity / strength. If the number is more than eight, the number of prepregs becomes too large, resulting in poor workability and cost. .

  When the present invention is applied to a golf club shaft, the weight (g) / shaft length (mm) of the tubular body is preferably 0.025 g / mm or more and 0.050 g / mm or less. This is because if it is less than 0.025 g / mm, it cannot be produced with an existing high-strength material, and even if it can be produced, it cannot have sufficient strength to withstand use, and if it exceeds 0.050 g / mm. This is because the lightness of the shaft cannot be maintained. Furthermore, the lower limit of the weight per unit of the tubular body is preferably 0.026 g / mm or more, particularly preferably 0.027 g / mm or more, and the upper limit is preferably 0.048 g / mm or less, particularly 0.045 g / mm or less.

  When the present invention is applied to a golf club shaft, the length of the tubular body is preferably 460 mm or more and 1220 mm or less in accordance with the official rules.

  The reinforcing fiber used in the prepreg is preferably a carbon fiber because it has a small specific gravity and a high elastic modulus and strength. However, other fibers that are generally used as a high-performance reinforcing fiber, such as glass fiber, aramid fiber, and boron. Fibers, alumina fibers, graphite fibers, silicon carbide fibers and the like can also be used.

Examples of the matrix resin used for the prepreg include a thermosetting resin and a thermoplastic resin, and the thermosetting resin is preferable from the viewpoint of strength and rigidity.
Examples of the thermosetting resin include epoxy resins, unsaturated polyester resins, phenol resins, melamine resins, urea resins, diallyl phthalate resins, polyurethane resins, polyimide resins, silicon resins, and the like. Among these resins, the epoxy resin is preferably used.
As thermoplastic resins, polyamide resins, saturated polyester resins, polycarbonate resins, ABS resins, polyvinyl chloride resins, polyacetal resins, polystyrene resins, polyethylene resins, polyvinyl acetate resins, AS resins, methacrylic resins , Polypropylene resin, fluorine resin and the like. Among these resins, the polyamide resin is preferably used.

  As described above, according to the present invention, a hoop prepreg that is difficult to wind by itself is formed as a laminated body that is laminated and adhered in advance to a base prepreg such as a straight prepreg or a bias prepreg that is easy to wind. By winding this laminated body around the core material, it is possible to prevent stacking failure such as hoop prepreg unwinding without increasing the number of windings of the base prepreg, and to reduce the weight of the tubular body, improve the strength, and improve the productivity. be able to.

  Further, at least one of both end edges and winding end edges in the tubular body axial direction of the laminated hoop previously integrated with the base prepreg is made to coincide with the peripheral edge of the base prepreg, or the base rather than the peripheral edge of the base prepreg By positioning it inside the prepreg, the anchor effect by the peripheral edge of the base prepreg is further exhibited, and stacking faults of the hoop prepreg can be more reliably prevented.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 4 show a tubular body 10 for a golf club shaft according to a first embodiment of the present invention.
The tubular body 10 is composed of a laminated laminate of eight fiber reinforced prepregs 20 (21 to 28), and both ends of the tubular body 10 are cut to required dimensions to produce a shaft 10 ′ as a final product.
As shown in FIG. 2, the shaft 10 ′ has a head 13 attached to a small-diameter head-side tip portion 11, and a grip 14 attached to a large-diameter-side grip-side rear end portion 12.

  In this embodiment, the total length of the shaft 10 'is 1130 mm, and the tubular body 10 is set to 1168 mm longer than the shaft 10'.

  The fiber reinforced prepreg 20 (21 to 28) uses carbon fibers for the reinforcing fibers F21 to F28, and uses an epoxy resin as a matrix resin.

Specifically, as shown in FIG. 1, the first and second sheets are bias prepregs 21 and 22, and the orientation angles of the reinforcing fibers F21 and F22 with respect to the axial direction of the tubular body 10 are −45 degrees and +45 degrees. It is said. The bias prepregs 21 and 22 have a length that is the entire length of the tubular body 10, a head side width of 50 mm, and a grip side width of 100 mm. The thickness is 0.085 mm and the resin content is 24%. The tensile elastic modulus of the reinforcing fibers F21 and F22 is 30 ton / mm ² .

The third sheet is a straight prepreg 23, and the orientation angle of the reinforcing fiber F23 is set to 0 degree with respect to the axial direction of the tubular body 10. The length is the total length (1168 mm) of the tubular body 10, the width on the head side is 26 mm, and the width on the grip side is 52 mm. The thickness is 0.082 mm and the resin content is 24%. The tensile elastic modulus of the reinforcing fiber F23 is 24 ton / mm ² .

The fourth sheet is a hoop prepreg 24, and the orientation angle of the reinforcing fiber F24 with respect to the axial direction of the tubular body 10 is 90 degrees. The length is 1128 mm, the width on the head side is 28 mm, the width on the grip side is 52 mm, the thickness is 0.034 mm, and the resin content is 40%. The tensile elastic modulus of the reinforcing fiber F24 is 30 ton / mm ² .

The fifth sheet is a straight prepreg 25, and the orientation angle of the reinforcing fiber F25 with respect to the axial direction of the tubular body 10 is 0 degree. The length is the entire length of the tubular body 10, the width on the head side is 27 mm, the width on the grip side is 53 mm, the thickness is 0.103 mm, and the resin content is 24%. The tensile elastic modulus of the reinforcing fiber F25 is 24 ton / mm ² .

  The fourth hoop prepreg 24 is a laminated hoop integrated with a fifth straight prepreg 25 in advance, and the laminated hoop prepreg 24 and the base prepreg straight prepreg 25 constitute a laminated body A1. . The length of the laminated hoop 24 is 1128 mm, the length of the straight prepreg 25 is 1168 mm, and both ends of the laminated hoop 24 in the length direction are located on the inner side from both ends in the length direction of the straight prepreg 25.

The sixth sheet is a hoop prepreg 26, and the orientation angle of the reinforcing fiber F26 with respect to the axial direction of the tubular body 10 is 90 degrees. The length is 1128 mm, the width on the head side is 29 mm, the width on the grip side is 53 mm, the thickness is 0.034 mm, and the resin content is 40%. The tensile elastic modulus of the reinforcing fiber F26 is 30 ton / mm ² .

The seventh sheet is a straight prepreg 27, and the orientation angle of the reinforcing fiber F27 with respect to the axial direction of the tubular body 10 is 0 degree. The length is the entire length of the tubular body 10, the width on the head side is 28 mm, the width on the grip side is 54 mm, the thickness is 0.082 mm, and the resin content is 24%. The tensile elastic modulus of the reinforcing fiber F27 is 24 ton / mm ² .

  The sixth hoop prepreg 26 is a laminated hoop previously integrated with the seventh straight prepreg 27, and the hoop prepreg 26 of the laminated hoop and the straight prepreg 27 of the base prepreg constitute a laminated body A2. . The length direction of the laminated hoop 26 is 1128 mm, the length of the straight prepreg 27 is 1168 mm, and both ends in the length direction of the laminated hoop 26 are located on the inside from both ends in the length direction of the straight prepreg 27.

The eighth sheet is a straight prepreg 28, and the orientation angle of the reinforcing fiber F 28 is 0 degree with respect to the axial direction of the tubular body 10. The length is 250 mm, the head side width is 100 mm, and the grip side width is 0 mm. The thickness is 0.082 mm and the resin content is 24%. The tensile elastic modulus of the reinforcing fiber F28 is 24 ton / mm ² .

Next, a method for manufacturing the tubular body 10 will be described.
The tubular body 10 is produced by a sheet winding method.
First, before the prepreg is wound around the cored bar (mandrel) and laminated, as shown in FIG. 3, the hoop prepreg 24 is a laminated hoop, and is laminated and adhered in advance to the straight prepreg 25 of the base prepreg. A stacked body A1 is prepared. Similarly, the hoop prepreg 26 is also formed as a laminated hoop, and a laminated body A2 is prepared by being laminated and adhered in advance to the straight prepreg 27 of the base prepreg.

When creating the laminate A1, as shown in FIG. 3, both end edges 24a, 24b in the tubular body axial direction of the hoop prepreg 24 of the laminated hoop are both end edges 25a in the tubular body axial direction of the straight prepreg 25 of the base prepreg, The first end edge 24c and the end edge 24d in the winding direction of the hoop prepreg 24 are positioned 20 mm inward from 25b, and the first end edge 25c and the end edge 25c in the winding direction of the straight prepreg 25 are positioned 1 mm inside. And the said both-ends edge 24a, 24b of the hoop prepreg 24 is located 10 mm inside from the both-ends cut position 15 and 16 of the tubular body 10, as shown in FIG. Positioning in this way, the two prepregs are bonded together and integrated.
When producing the laminated body A2, the hoop prepreg 26 of the laminated hoop is bonded to the inner side of the straight prepreg 27 of the base prepreg and to the inner side of the tubular body final cut positions 15 and 16. Integrate.

After creating the laminates A1 and A2, the prepregs 20 (21 to 28) are sequentially wound around a core bar (not shown) and laminated.
First, the bias prepregs 21 and 22 and the straight prepreg 23 are sequentially wound around the metal core, and then the laminate A1 is wound so that the hoop prepreg 24 is on the inner peripheral side and the straight prepreg 25 is on the outer peripheral side. Next, the laminate A2 is wound so that the hoop prepreg 26 is on the inner peripheral side and the straight prepreg 27 is on the outer peripheral side.
Finally, the straight prepreg 28 is wound around the head side tip and laminated.

  Next, the surface of the laminate of prepregs 21 to 28 is wrapped with a tape made of polyethylene terephthalate resin or the like, and heated and pressed in an oven to cure the resin, and integrally molded, and then the core metal is pulled out, A tubular body 10 is formed.

  As described above, the tubular body 10 is straight in the state of the laminated bodies A1 and A2 in which the hoop prepregs 24 and 26 are not wound alone in the manufacturing process, but are laminated and adhered in advance to the straight prepregs 25 and 27 to be the base prepregs. It is wound together with the prepregs 25 and 27. In this way, the hoop prepregs 24 and 26 can be easily wound without particularly increasing the number of windings of the straight prepregs 25 and 27 serving as the base prepreg, and the hoop prepregs 24 and 26 are suppressed while suppressing an increase in the weight of the tubular body 10. Can be prevented from being peeled off and poor stacking.

  Moreover, since the laminated bodies A1 and A2 are arranged so that the hoop prepregs 24 and 26 of the laminated hoop do not protrude from the peripheral edges of the straight prepregs 25 and 27 of the base prepreg, the anchor effect of the straight prepregs 25 and 27 is further increased. The hoop prepregs 24 and 26 can be more reliably prevented from being peeled off.

  Furthermore, since both end edges 24a, 24b, 26a, 26b of the hoop prepregs 24, 26 in the axial direction of the tubular body are positioned inside the both end cut positions 15, 16 of the tubular body 10, the shaft 10 which is the final product. The both end edges 24a, 24b, 26a, 26b of the hoop prepregs 24, 26 do not appear at both ends 17, 18 of the ', and both the end edges 24a, 24b, 26a of the both ends 17, 18 of the shaft 10' and the hoop prepregs 24, 26 appear. , 26b always includes a laminated contact portion of straight prepregs 25 and 27. Thereby, in particular, it is possible to effectively prevent the hoop prepregs 24 and 26 from being easily peeled off at both ends 17 and 18 of the shaft 10 '.

Further, the hoop prepregs 24 and 26 have a thickness in the range of 0.03 to 0.06 mm, and the tensile elastic modulus of the reinforcing fibers F24 and F26 in the range of 30 to 80 ton / mm ^2. Both strength and ease of winding can be provided in a balanced manner.

  Furthermore, since both the hoop prepregs 24 and 26 of the laminated hoops constituting the laminates A1 and A2 and the straight prepregs 25 and 27 of the base prepreg have a resin content within a range of 30 to 40%, a high lamination The increase in weight can be suppressed while preventing the hoop prepregs 24 and 26 from being peeled off by the adhesion.

(Example)
In order to confirm the above, Example 1 and Comparative Example 1 of the golf club shaft tubular body according to the present invention will be described in detail. In addition, although the effect of this invention is clarified by the Example, this invention is not limited based on description of this Example.

  Example 1 and Comparative Example 1 were prepared by differentiating only the winding method around the core material of the hoop prepreg, and evaluated for the presence or absence of poor adhesion.

  In Example 1 and Comparative Example 1, the fiber angle and shape of the fiber-reinforced prepreg used were the same as those in the first embodiment. That is, the bias prepregs 21 and 22, the straight prepreg 23, the hoop prepreg 24, the straight prepreg 25, the hoop prepreg 26, the straight prepreg 27, and the straight prepreg 28 were wound around a core material and manufactured by a sheet winding manufacturing method. In Example 1 and Comparative Example 1, the total length was 1168 mm and the weight was 45 g.

In Example 1 and Comparative Example 1, the specifications of the prepregs 21 to 28 were the same. Specifically, prepregs manufactured by Toray Industries, Inc. using carbon fibers as reinforcing fibers are used for all the prepregs 21 to 28 as shown in Table 1. That is,
In the bias prepregs 21 and 22, the fiber type is M30S, the resin type is # 2521R, the tensile elastic modulus of the fiber is 30 ton / mm ² , the thickness is 0.085 mm, and the resin content (weight ratio of the prepreg) is 24%.
In the straight prepreg 23, the fiber type is T700G, the resin is # 2521R, the tensile elastic modulus of the fiber is 24 ton / mm ² , the thickness is 0.082 mm, and the resin content is 24%.
In the hoop prepregs 24 and 26, the fiber type is M30S, the resin type is # 2500, the tensile elastic modulus of the fiber is 30 ton / mm ² , the thickness is 0.034 mm, and the resin content is 40%.
In the straight prepreg 25, the fiber type is T700G, the resin type is # 2521R, the tensile elastic modulus of the fiber is 24 ton / mm ² , the thickness is 0.103 mm, and the resin content is 24%.
In the straight prepregs 27 and 28, the fiber type is T700G, the resin type is # 2521R, the tensile elastic modulus of the fiber is 24 ton / mm ² , the thickness is 0.082 mm, and the resin content is 24%.

Example 1
The winding method of the hoop prepregs 24 and 26 is the same as that in the first embodiment. That is, the hoop prepreg 24 of the laminated hoop was preliminarily laminated and adhered to the straight prepreg 25 of the base prepreg to produce a laminate A1. The hoop prepreg 26 of the laminated hoop was laminated and adhered in advance to the straight prepreg 27 of the base prepreg to produce a laminate A2.
The prepregs 21, 22, and 23, the laminates A1 and A2, and the prepreg 28 were wound around the core material in this order. The laminates A1 and A2 are laminated so that the hoop prepregs 24 and 26 of the laminate hoops are not protruded from the peripheral edges of the straight prepregs 25 and 27 of the base prepreg, and are wound so that the hoop prepregs 24 and 26 are on the inner peripheral side. Wearing.

(Comparative Example 1)
The prepregs 21 to 28 were wound around the core material sequentially from the inner peripheral side. Accordingly, the hoop prepregs 24 and 26 were also wound one by one.

(Evaluation of adhesion failure)
50 each of Example 1 and Comparative Example 1 were produced, and in the production process, a visual appearance check of the wound state was performed after each prepreg was wound, and adhesion failure (lifting from the lower layer) at the end of the prepreg was confirmed. Then, for those in which defects were found, the next prepreg was wound after the contact work was performed again, and the entire winding was completed.
The evaluation results showed that there was no adhesion failure in all 50 windings for Example 1, but for Comparative Example 1, 13 out of 50 hoop prepregs 24 and / or hoop prepregs 26 A poor adhesion was found in the winding.

It is a figure which shows the laminated structure of the fiber reinforced prepreg of the tubular body for golf club shafts which concerns on 1st Embodiment of this invention. It is the schematic of the golf club shaft which is a final product. It is a top view which shows a lamination | stacking prepreg. It is a top view which shows the both ends of a tubular body. It is sectional drawing which shows the prepreg laminated structure of a prior art example.

Explanation of symbols

10 Tubular body 10 'Golf club shaft (final product)
20 Fiber reinforced prepreg 21, 22 Bias prepreg 23, 25, 27, 28 Straight prepreg 24, 26 Hoop prepreg A1, A2 Laminate

Claims (6)

In the method for producing a tubular body made of a fiber reinforced resin comprising a laminate of prepregs obtained by impregnating a reinforcing fiber with a matrix resin,
Bias prepreg in which the arrangement direction of the reinforcing fibers is inclined with respect to the tubular body axis, a straight prepreg in which the arrangement direction of the reinforcing fibers is arranged in parallel to the tubular body axis, and the arrangement direction of the reinforcing fibers are tubular A step of winding a hoop prepreg arranged at right angles to the body axis on a core material;
At least one of the hoop prepregs is formed as a laminated hoop prepreg by previously laminating and adhering to a base prepreg composed of the bias prepreg or the straight prepreg and forming a laminated body and winding the laminated body to form the base. A method for producing a fiber-reinforced resin tubular body, wherein the laminated hoop prepreg is wound integrally with a prepreg.   At least one of the both ends and winding end edges in the tubular body axial direction of the laminated hoop prepreg which is laminated and adhered to the base prepreg is aligned with the peripheral edge of the base prepreg, or located inside the peripheral edge of the base prepreg. A method for producing a fiber-reinforced resin tubular body according to claim 1. A tubular body manufactured by the method according to claim 1 or 2,
Both ends of the laminated hoop prepreg in the tubular body axial direction are tubular bodies made of fiber reinforced resin that are located inside the axial end positions of the tubular body. The laminated hoop prepreg is a tubular body made of fiber reinforced resin according to claim 3, wherein the thickness is 0.03 to 0.06 mm and the tensile elastic modulus of the reinforcing fiber is 30 to 80 ton / mm ² .   The tubular body made of fiber-reinforced resin according to claim 3 or 4, wherein the resin content of the laminated hoop prepreg and / or the base prepreg is 30 to 40%.   The tubular body made of a fiber reinforced resin according to any one of claims 3 to 5, comprising a golf club shaft.

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